This application is based on Patent Application No. 2001-171133 filed Jun. 6, 2001 in Japan, the content of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to an IC socket for connecting contacts of a socket body to external terminals of an IC package, an electronic part, and more particularly to an IC socket which has edge moving mechanisms for positioning an IC package placed on a platform.
2. Description of the Related Art
Among conventional IC sockets that receive a package for electronic parts as an electrical components, particularly an IC package, there is known an IC socket which makes an electric connection with solder balls that constitute external terminals of the IC package to be mounted on a base plate of the socket body.
In such a conventional IC socket, a center of the IC socket is positioned in such a manner to be aligned with a center of the IC package by adjusting positions of IC package positioning portions at four sides of the IC socket. Hence, the center positions of the positioning portions of the IC socket may deviate horizontally or vertically, making it difficult to make contacts at the same positions at all times. There may arise a positioning where the contacts of the socket body fail to contact with the solder balls of the IC package.
To solve these problems experienced with the conventional IC sockets, it is therefore an object of the present invention to provide an IC socket in which a plate spring is provided with a latch lever which has an edge moving mechanism. Immediately before the latch lever is fully closed, the plate spring operates to move the IC package from one side to the other in order to position the IC package.
In order to achieve the above object, the IC socket of the present invention comprises, in an open top type of the IC socket having a plurality of pin type contacts for electrical connection with an IC package inserted into the IC socket, a socket body having a base plate, a vertically movable cover, a platform attached to the base plate and having an IC package mounting portion, and edge moving mechanisms each having a latch lever for holding the IC package placed on the platform and adapted to move the IC package from one side to an opposite side for a positioning of the IC package. With this construction, the IC package can be moved from one side to the other by the plate spring for a positioning before the latch lever is fully closed.
Further, in the IC socket of the present invention, since the edge moving mechanisms are located at almost the centers of the two adjoining sides of the IC socket respectively, the numbers of dimensional controlling portions for the positioning portions between the contacts and the IC package reduces from four to two and time taken for adjusting check the positioning portion is shortened to improve the efficiency of task.
Furthermore, in the IC socket of the present invention, the edge moving mechanisms each has a plate spring provided on the underside of the latch lever, has an outer end of the latch lever pivotally supported on the IC socket and holds the IC package between an inner end of the latch lever and the platform, and therefore the edge moving mechanisms can be formed in a simple construction comprising the latch lever and the plate spring.
Further, in the IC socket of the present invention, the plate spring engages the molded portion of the IC package and moves it from one side to the other before the latch lever is fully closed, and therefore the IC package can be correctly positioned and held by the latch lever.
Because the edge moving mechanisms of the IC socket of the present invention are arranged by selecting one of corner portions of the IC package mounting portion as a reference fixed positioning portion, the number of dimensional controlling portions required for establishing a positional alignment between the contacts and the IC package decreases from four portions to two, which make it possible to shorten the time it takes to adjust the positioning portions and improves the positioning operation efficiency.
Furthermore, since the IC package of the present invention is of a ball grid array type(BGA) or a land grid array type(LGA), the IC socket can accept the IC package properly and be formed in a simple construction.
Other objects, features and advantages of the present invention will become more apparent from the following detailed description on the IC socket of one embodiment thereof taken in conjunction with the attached drawings.